That is so unusual. I wonder if the buttons are being pushed off because the text for the path was so long. I could just change that to only display the backup file name instesad of the path to the file. What do you think of that? Do people care about seeing the full path to the file they just selected?

I'll look at that dialog in detail to see if there are any adjustments that can be made to ensure the buttons are visible. Do any other dialogs have the same issue? Does the backup library dialog have the same problem? I ask because it's implemented in the same way as the restore dialog. If they both have the same problem, the only way for me to fix the issue is probably to use a trick where I load a separate activity/screen when you tap backup or restore, and that activity then pops up a normal dialog. At the moment, I'm using an option where you can have a separate activity show up as a dialog instead of a separate screen. It's possible that causes issues on certain devices.

Keeping the path is imho better than just showing the filename.
To avoid problems when it takes too much space better limit it in size or length by replacing something in the middle or at the beginning with "..."